Windows Identity Foundation is part of Microsoft’s identity and access management solution built on Active Directory that also includes:

Active Directory Federation Services 2.0 (AD FS 2.0) a security token service for IT that issues and transforms claims and other tokens, manages user access and enables federation and access management for simplified single sign-on.

Windows CardSpace 2.0 Beta 2: the end user component of Microsoft’s user access platform for developers and IT professionals that helps simplify access to applications and other systems with an open claims-based model.